Pepper spray or oleoresin capsicum (OC) is used by law enforcement and corrections agencies across the Nation to subdue dangerous individuals. This report summarizes the results of two unpublished National Institute of Justice (NIJ) funded studies on the safety and effectiveness of pepper spray in real-life arrests and compares these studies with prior studies. The intent of this report was to broaden the scope of knowledge relating to pepper spray and for law enforcement policymakers and practitioners, defense and prosecution attorneys involved in pepper spray cases, as well as medical examiners. Claims of pepper spray’s effectiveness were tested in three North Carolina police jurisdictions, before and after the pepper spray was introduced. Results of this study found that the number of injuries to police officers and suspects declined after pepper spray was introduced. In addition, complaints regarding the police used excessive force declined. The second studied 63 cases of in-custody deaths following pepper spray use in hopes of determining the role played by pepper spray. Results of this study indicated that pepper spray did not cause or contribute to death in 61 out of 63 cases. Also, pepper spray was not found to be effective in any of the cases of position asphyxia and its precise role could not be determined. Study limitations are discussed and include: (1) in the North Carolina study, procedures for identifying officer and suspect injuries differed from agency to agency and over time with each agency; (2) in the in-custody deaths, the identification of trends was difficult due to the pepper spray used in the arrest process being very low; and (3) each arrest situation is unique making it difficult to near impossible to collect enough identical arrest scenarios.